EXCLUSIVE: 'Fixer Upper' star Joanna Gaines explains why her kids don't have cell phones

Joanna Gaines and husband Chip have become megastars, thanks to the success of their wildly popular HGTV show, Fixer Upper, but they've held steadfast to their down-home ways, as ET found out during our visit to the family's farm.

The 40-acre spread in Texas includes everything from turkeys to longhorn cattle, giving Chip and Joanna's four children (Drake, Ella, Duke and Emmie) plenty to keep busy, but there's one thing their children don't have.

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"I tell the kids that you are probably not going to get a cell phone," Joanna told ET. "We want to teach our kids that life happens outside of these devices. It's just a simple thing to go outside and connect with nature, play with your friends and get dirty."

The family also doesn't own a TV, but that hasn't stopped them from having HGTV's No. 1 home improvement show, now entering its fourth season.

"It's the simple things," Joanna said.

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What they lack in electronics, the family more than makes up for in nearly every other category, namely clothes, which is Joanna's latest passion. She's teamed up with Matilda Jane Clothing to design a collection of girls' clothes with her two daughters in mind.

"It's funny. The girls will come in my closet and they always say, 'Hey, when I get older, can you save this dress for me? Can you save these shoes for me?' So I thought it would be sweet to do a cute little mommy-and-me thing, even with just the aprons," she said.

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Fixer Upper airs at 9 p.m. ET/PT on HGTV.